Optical code scanners are used in point of sale (POS) terminals to read optical codes on items which are presented to the POS terminals for purchase as part of a purchase transaction. As part of the purchase transaction, a customer may present coupons or other documents that include optical codes which must be read. Optical code scanners use image based scanning technology to scan optical codes through one or more scanning windows. Image based scanning technology captures an image of an optical code presented to the optical code scanner through one of the scanning windows. The optical codes being presented may be printed on a substrate or displayed on a display of a portable electronic device. However, image based scanning technology must be optimized for the method in which the optical code is being presented or the optical code scanner will fail to read the optical code which slows down the purchase transaction.